I have read in several places that when making cane or rose shoot arrows that the wider base of the arrow is used at the tip. One of the benefits of this being that spine is less of an issue. if this is a product of the taper would that then hold true for wooden arrows. if thery were tapered from one end to the other and the thick end put at the tip would spine still be as big an issue.
Spine is always an issue, regardless of material. Putting the thicker part of the shaft toward the point increases FOC, i.e., puts the heavier portion of the shaft forward. That makes for a more stable/aerodynamic shaft than one in which the heavier portion of the shaft is rearword. Spine can be a little more off with the weight forward arrow than the weight rearword arrow, but it's still important to have the spine correct for a particular bow.